According to the baby's great-grandfather, Eddie Markhouse, his granddaughter is not lying.

"I don't know the whole story. But, from what I understood, she met him at a concert and he sent two security guards down off of the stage to bring her backstage to meet him," Markhouse said in an interview with Inside Edition.

"She said they partied, had some drinks and they indulged in sex… She's basically an honest good person. She's got a big heart. She's a good kid and she loves this baby."

The 20-year-old San Diego native has reportedly filed a paternity suit against the chart-topper, alleging that he is the father of her 3-month-old baby, Tristyn Anthony Markhouse Yeater.

According to a little research done by Fox News, Yeater was on food stamps when she was plucked from the front row of a Bieber concert in Los Angeles by his bodyguards to meet the star backstage late last year.

Court documents also reveal that Yeater dropped out of high school and has only held a job for two months earlier this year. She also has no source of income and has never filed a tax return with the State of California or the IRS. She gave birth to her son on July 6 of this year, claiming that the birth cost her $25,000. She does however receive $500 per month in public assistance.

Yeater is asking the court to force Bieber to take a DNA test before he can simply say, "the kid is not my son."